-
针对2009年11月冰冻雨雪事件,通过经验正交函数分解等方法提取10-30 d稳定分量, 并第一次运用计算贡献率和相似系数判定等手段把稳定分量进一步客观地分离成气候态稳定分量 和异常型稳定分量.将气候态稳定分量与低通滤波分量合成气候背景场.研究发现: 气候背景场环流形势持续时间较长,随时间变化缓慢,主要提供了事件发生的气候背景, 指示大尺度环流调配置和调整;气候背景场空间活动范围较大,能较好地刻画永久半永久性大气活动中心 变化情况,且在垂直各层有稳定一致的配置关系;异常型稳定分量重点体现了环流相对异常特征, 与2009年11月冰冻雨雪事件有较好的对应关系.在气候背景场提供确定的环流大背景下, 异常型稳定分量表征了对应天气系统的相对强弱变化.In this paper, we extract stable components in extended-range forecasting for the coming 10-30 days by using empirical orthogonal function analysis and some other methods during the snow storm event in November 2009. At the first time, stable components in extended-range forecasting for the coming 10-30 days can be divided into two parts: climatic stable components and abnormal stable components, by contribution rate analysis, similarity coefficient and so on. We combine climatic stable components and low-pass filter components to obtain climatological background field. The results show as follows. 1) The circulation pattern of climatological background field persists for a long time and changes slowly. It provides climatological background for the weather event mainly. 2) The climatological background field can indicate the fluctuations of semi-permanent or permanent center with a large space scales. The climatological background field cooperates well in vertical divisions. 3) The abnormal stable components reflect abnormal circulation, and the circulation pattern of abnormal stable components corresponds to the snow storm event in November 2009 well on the time scale. The climatological background field represents circulation pattern background and the abnormal stable components represent the relative strength of weather system.
[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] -
[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23]
计量
- 文章访问数:5971
- PDF下载量:493
- 被引次数:0
下载: